On Thu, 20 Aug 2009 14:08:55 +0200, "bgimeno" <bgimeno[at]persistencia[dot]org>
wrote:

> the use of this first superfluous rand()  affects the values extracted by 
>the 2nd and 3rd rand(). In this case therefore we obtain values that don't 
>seem to follow any pattern.
>Be recorded as comment on the peculiarities of the rand () function and 
>nothing else.

/*
Try this extract of your scene. By commenting out some #declare RotNo2's you
will get different results :)
/* 

#include "colors.inc"

camera {location <0,150,-150>
        look_at <0,0,0>
       }
light_source {<50,300,-100> colour White}
light_source {<-150,300,-100> colour White}

#declare Tree =  sphere {<0,0,0>2 pigment {White} } ;

#declare Num_Tree = 0 ;        

// ------------------------------------------------------
#while (Num_Tree<5000)
  #declare rnd_tree = seed (Num_Tree);
  object {Tree  
#declare rnd_tree = seed (Num_Tree);

          translate x*60       // code C 

// Comment out the lines below to get different effects
#declare RotNo2 = rand(rnd_tree); 
#declare RotNo2 = rand(rnd_tree); 
#declare RotNo2 = rand(rnd_tree);
#declare RotNo2 = rand(rnd_tree);
#declare RotNo2 = rand(rnd_tree);

                   
         
          
          rotate <0,rand(rnd_tree),rand(rnd_tree)>*360
          
          }
  #declare Num_Tree = Num_Tree +1 ;
#end

-- 

Regards
     Stephen

Post a reply to this message